1. Field of the Invention
The present invention relates to a dust cover and locking assembly for an electrical or fiber optic connector.
2. Description of the Related Art
Dust covers are desirable for preventing contamination of the exposed ends of electrical, pneumatic, or fiber optic connectors when mating connectors are not connected thereto. Optical fibers are especially sensitive to contamination since they are typically smaller than 100 microns in diameter. A single particle of dirt or dust on the end of an optical fiber in a connector can seriously damage and/or completely block light transmission through the connector. The contacts of electrical connectors are sensitive to corrosion through exposure the atmosphere.
Conventional dust covers are connected to their respective connectors in the same manner as the mating connectors; i.e. threaded or bayonet connections, and are retained near the connectors by lanyards or chains.
The main problem with this arrangement is that the dust covers are a nuisance to attach to the connectors, and are often left unattached due to thoughtlessness or neglect. Also, conventional dust covers are subject to loosening caused by vibration, allowing air and other contaminants to enter the connector.
A number of dust covers which are movable into operative positions when a mating connector is disconnected from a fixed connector have been proposed in the prior art. A typical example is found in U.S. Pat. No. 3,659,248, entitled "COMBINED SOCKET COVER AND PLUG RETAINER", issued Apr. 25, 1972 to F. Mann et al. This patent discloses a plastic member provided with a hinge which is attached to a supporting wall next to an electrical socket. The plastic member is provided with a retaining flange spaced from the hinge. When the socket is empty, the member can be pivoted on its hinge down over the socket, and can be held by the retaining flange so as to serve as a cover for the socket. When a plug is to be inserted into the socket, the member can be pivoted on its hinge so that the retaining flange can engage the plug so as to serve as a plug retainer.
U.S. Pat. No. 4,312,553, entitled "ELECTRICAL CONNECTION DEVICE", issued Jan. 26, 1982 to R. Lyckesjo, improves on the Mann arrangement by spring loading a cover which corresponds to Mann's plastic member, and providing it with a seal so that it is automatically moved into sealing engagement with the socket when the plug is removed therefrom.
U.S. Pat. No. 4,779,950, entitled "CONNECTION APPARATUS FOR OPTICAL FIBERS", issued Oct. 25, 1988 to R. Williams, discloses an optical fiber connection apparatus including a pair of mating connector halves, each accommodating at least one optical fiber. A plug half is insertable into a receptacle half to provide optical connection between the fibers therein. The receptacle portion includes a movable cover supported thereon. The cover is movable from a first position covering the receptacle and thereby protecting the fiber therein to a second position opening the receptacle to allow for insertion of the plug. The cover is also movable to lock the plug into the receptacle.
Although Williams' movable cover protects the optical fiber when the plug is disconnected from the receptacle, there is a gap between the cover and a side wall of the receptacle when the plug and receptacle are connected, into which dirt and dust can enter. These contaminants may be transferred from the cover to the end face of the optical fiber when the plug is disconnected from the receptacle, with damaging results.